In the prior art, to measure the azimuth or the elevation of a target in an electronic scanning system a repetition frequency, which pulses are either unmodulated or phase modulated in accordance with a code; alternatively, a first group of a series of adjacent rf pulses is transmitted in which constituent pulses of each series are phase modulated in accordance with a code and transmitted within a prf interval. This first group is transmitted along a first beam and the corresponding group of returns from the target received along this frst beam are processed, a second identical group of rf pulses next is transmitted along a second beam which overlaps the first beam within the expected target direction and the corresponding group of target returns received along the second beam are subsequently processed. The period of transmission and reception of both groups of transmitted and received pulses together form a target acquisition cycle. The ratio of the two processed group returns provides a measure of the direction of the target. This technique is of sufficient accuracy only for targets which present the same cross section to the transmitter during the interval between the first and last pulses of the pulse groups and for targets which do not change appreciably in azimuth, elevation, range and velocity (doppler frequency change) during this time interval.